/*
 * ***** BEGIN GPL LICENSE BLOCK *****
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * ***** END GPL LICENSE BLOCK *****
 */

/** \file blender/blenkernel/intern/editmesh_cache.c
 *  \ingroup bke
 *
 * Manage edit mesh cache: #EditMeshData
 */

#include "MEM_guardedalloc.h"

#include "DNA_mesh_types.h"

#include "BLI_math.h"

#include "BKE_editmesh.h"
#include "BKE_editmesh_cache.h"  /* own include */

void BKE_editmesh_cache_ensure_poly_normals(BMEditMesh *em, EditMeshData *emd)
{
	if (!(emd->vertexCos && (emd->polyNos == NULL))) {
		return;
	}

	BMesh *bm = em->bm;
	const float (*vertexCos)[3];
	float (*polyNos)[3];

	BMFace *efa;
	BMIter fiter;
	int i;

	BM_mesh_elem_index_ensure(bm, BM_VERT);

	polyNos = MEM_mallocN(sizeof(*polyNos) * bm->totface, __func__);

	vertexCos = emd->vertexCos;

	BM_ITER_MESH_INDEX (efa, &fiter, bm, BM_FACES_OF_MESH, i) {
		BM_elem_index_set(efa, i); /* set_inline */
		BM_face_calc_normal_vcos(bm, efa, polyNos[i], vertexCos);
	}
	bm->elem_index_dirty &= ~BM_FACE;

	emd->polyNos = (const float (*)[3])polyNos;
}

void BKE_editmesh_cache_ensure_vert_normals(BMEditMesh *em, EditMeshData *emd)
{
	if (!(emd->vertexCos && (emd->vertexNos == NULL))) {
		return;
	}

	BMesh *bm = em->bm;
	const float (*vertexCos)[3], (*polyNos)[3];
	float (*vertexNos)[3];

	/* calculate vertex normals from poly normals */
	BKE_editmesh_cache_ensure_poly_normals(em, emd);

	BM_mesh_elem_index_ensure(bm, BM_FACE);

	polyNos = emd->polyNos;
	vertexCos = emd->vertexCos;
	vertexNos = MEM_callocN(sizeof(*vertexNos) * bm->totvert, __func__);

	BM_verts_calc_normal_vcos(bm, polyNos, vertexCos, vertexNos);

	emd->vertexNos = (const float (*)[3])vertexNos;
}

void BKE_editmesh_cache_ensure_poly_centers(BMEditMesh *em, EditMeshData *emd)
{
	if (emd->polyCos != NULL) {
		return;
	}
	BMesh *bm = em->bm;
	float (*polyCos)[3];

	BMFace *efa;
	BMIter fiter;
	int i;

	polyCos = MEM_mallocN(sizeof(*polyCos) * bm->totface, __func__);

	if (emd->vertexCos) {
		const float (*vertexCos)[3];
		vertexCos = emd->vertexCos;

		BM_mesh_elem_index_ensure(bm, BM_VERT);

		BM_ITER_MESH_INDEX (efa, &fiter, bm, BM_FACES_OF_MESH, i) {
			BM_face_calc_center_median_vcos(bm, efa, polyCos[i], vertexCos);
		}
	}
	else {
		BM_ITER_MESH_INDEX (efa, &fiter, bm, BM_FACES_OF_MESH, i) {
			BM_face_calc_center_median(efa, polyCos[i]);
		}
	}

	emd->polyCos = (const float (*)[3])polyCos;
}
